4-Jun-10 Barriers that use bubbles, strobe lights, and sound to guide Asian carp to isolated locations for further study are getting more attention by the U.S. Army Corps of Engineers as it continues to find ways to fight the large, hungry, prolific fish.
Asian carp have been migrating north since the 1990s and once they reached the Great Lakes, it is believed they would disrupt the food chain.
A report made public on Thursday supports construction of a third electric fish barrier 70 miles downstream from the Chicago River. Two barriers near Romeoville, Illinois, have been operational since 2008. The third barrier, paid for by the 2009 economic stimulus package, should be ready by the end of October.
At a news conference on Thursday afternoon, Major General John W. Peabody, commander of the USACE Great Lakes & Ohio River Division, said the barriers remain our best defense in keeping Asian carp from migrating into the Great Lakes.
Closing locks on the Chicago River, including one near Navy Pier, was being considered, but, says Peabody, temporary lock closures do very little to reduce the risk of Asian carp migration by themselves but they can enable other tools.
After conducting a thorough analysis of modifications to lock operations, Peabody announced, the report recommends intermittent lock operations on a case-by-case basis in support of fish management efforts, such as spot chemical applications or intensive commercial fishing efforts by U.S. Fish and Wildlife [Service] and Illinois Department of Natural Resources.
(Left) Major General John W. Peabody
Meanwhile, the collection and processing of e-DNA samples is picking up, even though traces of Asian carp e-DNA are rare. Since April, only three Asian carp fragments have been found in more than 400 samples. The Army Corps of Engineers is now collecting 60 samples per week up from 40 and hopes to move to 120 samples per week soon.
And results of a peer review of e-DNA research being done by the University of Notre Dame are expected in September. At that point, says General Peabody, we hope to be able to say with great clarity and confidence exactly what e-DNA tells us and what it doesnt tell us because we will have had the peer review that many have encouraged us to execute.
In April, the Illinois Chamber of Commerce estimated that closing the Chicago River locks would cost $4.7 billion over 20 years, including $537 million in each of the first eight years. The Illinois Corn Growers Association estimated closure of the locks would add $500 million per year in transportation costs.